The invention relates generally to welding systems and, more specifically, to multiple drives in a wire feed welding system.
Welding systems sometimes include multiple wire drives to feed a welding wire to a torch. Unfortunately, the multiple wire drives are often out-of-synchronization, thereby causing compression or tension in the welding wire passing between the multiple wire drives. If the welding wire is in compression between the multiple wire drives, then the welding wire can buckle or coil like a spring. Unfortunately, the coiling of the wire can cause random directional changes in the wire feed trajectory, thereby making welding more difficult or impossible. If the columnar strength of the wire is exceeded while in compression, then the welding wire can buckle causing a wire jam and failure of the system. If the welding wire is in tension between the multiple wire drives, then the welding wire may become deformed due to compaction, stretching, or shaving. Again, the wire deformation can cause random directional changes in the wire feed trajectory, thereby making welding more difficult or impossible. Excessive tension in the welding wire can also cause drive roll slippage in each of the multiple wire drives, thereby causing inconsistencies in the amount of wire delivered to the welding arc. The wire tension can also cause failure of the welding wire drives, for example, due to excessive motor current and excessive wear of the gears and bearings. Unfortunately, these problems with tension and compression in the welding wire are currently addressed by replacing the welding wire drives or separately calibrating the drives, which is both costly and time consuming. In addition, these solutions may require special equipment to identify and resolve the problem.